feat(firstleg): implement container customs workflow

scripts/admin-test-env-modules/README.md

@@ -62,6 +62,7 @@ export async function run(context) {
 | 入库测量、首次打印冻结箱码与墨家扫码 | `inbound-measurement.mjs` | `inbound-measurement-box-code-contract.test.mjs` |
 | 入仓自动头程费用、派生详情、人工发布与 MANUAL 其他费用版本 | `inbound-fees.mjs`（前置：`merchant-qualification-fixture,orders,inbound-measurement`） | `inbound-fees-contract.test.mjs` |
 | 三期模拟柜关联、柜次概览、渠道隔离、装柜模型桥接、PDA、动态增量、四类货柜资料、报关与证据/出仓门禁 | `phase3-container-loading.mjs`、`ocean-booking-fixture.mjs`、`phase3-container-overview.mjs`、`phase3-loading.mjs`、`phase3-loading-model-bridge.mjs`、`phase3-pda-convergence.mjs`、`phase3-evidence-gate.mjs`、`phase3-loading-finalize.mjs`、`phase3-container-documents.mjs`、`phase3-customs.mjs`、`phase3-outbound-dispatch.mjs` | `container-simulation-association-contract.test.mjs`、`container-specification-fixture-contract.test.mjs`、`ocean-booking-channel-contract.test.mjs`、`phase3-container-regression-contract.test.mjs`、`phase3-loading-model-bridge-contract.test.mjs`、`phase3-loading-dynamic-final-contract.test.mjs`、`phase3-container-documents-contract.test.mjs`、`phase3-phase4-departure-pickup-chain-contract.test.mjs`、`phase3-producer-chain-contract.test.mjs`、`manual-state-loading-pda-contract.test.mjs` |
+| 头程整柜报关（待最终HTTP契约对齐） | `phase3-container-customs.mjs`（全买单、纯退税、混合三柜；最终 Controller/OpenAPI 未齐时 fail-closed，不进入默认入口） | `container-customs-acceptance-contract.test.mjs`、`container-customs-acceptance-matrix.mjs` |
 | 分柜与父子入库单数量守恒 | `phase3-order-splitting.mjs` | `phase3-order-splitting-contract.test.mjs` |
 | 人工计划分柜准备与只读核验 | `manual-order-splitting-fixture.mjs`、`manual-order-splitting-verify.mjs`（可选，不进入默认全量） | `manual-order-splitting-contract.test.mjs` |
 | 人工推送预装前置与推送后只读核验 | `manual-preload-push-fixture.mjs`、`manual-preload-push-verify.mjs`（可选，不进入默认全量） | `manual-preload-push-contract.test.mjs` |